Count number of occurrences of two column cases

Question

I have a dataframe:

ID   col1  col2  
1    LOY    A
2    LOY    B
3    LOY    B
4    LOY    B
5    LOY    A

I want to count number of occurrences of unique values according to col1 and col2. So, desired result is:

event    count
loy-a      2
loy-b      3

How could i do that?

Answer 1

You can also try:

library(dplyr)
#Code
new <- df %>% group_by(event=tolower(paste0(col1,'-',col2))) %>%
  summarise(count=n())

Output:

# A tibble: 2 x 2
  event count
  <chr> <int>
1 loy-a     2
2 loy-b     3

Some data used:

#Data
df <- structure(list(ID = 1:5, col1 = c("LOY", "LOY", "LOY", "LOY", 
"LOY"), col2 = c("A", "B", "B", "B", "A")), class = "data.frame", row.names = c(NA, 
-5L))

Answer 2

Here is an option where we convert the columns to lower case, then get the count and unite the 'col1', 'col2' to a single 'event' column

library(dplyr)
library(tidyr)
df1 %>%
  mutate(across(c(col1, col2), tolower)) %>%
  count(col1, col2) %>%
  unite(event, col1, col2, sep='-')

-output

 #  event n
#1 loy-a 2
#2 loy-b 3

NOTE: Returns the OP's expected output

---

Or using base R

with(df1, table(tolower(paste(col1, col2, sep='-'))))

data

df1 <- structure(list(ID = 1:5, col1 = c("LOY", "LOY", "LOY", "LOY", 
"LOY"), col2 = c("A", "B", "B", "B", "A")), 
class = "data.frame", row.names = c(NA, 
-5L))